Low-level air pollution and incidence of asthma among adults

Abstract

TPS 684: Long-term health effects of air pollutants 1, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background/Aims: Air pollution has been linked to asthma onset in adults, yet few studies have investigated the effects of low-level pollution below current EU and WHO limit values or guidelines. Within the multicenter ‘Effects of Low-Level Air Pollution: A Study in Europe’ (ELAPSE) study, we examined the association of long-term exposure to fine particulate matter (PM2.5), nitrogen dioxide (NO2), black carbon (BC), and ozone (O3) with incidence of asthma in European adults. Methods: We pooled data from 2 cohorts from Denmark and Sweden harmonizing individual and area-level variables. Annual mean concentrations of PM2.5, NO2, BC and O3 were centrally modelled for Europe for 2010 by hybrid land use regression models (100 m resolution). We used stratified Cox proportional hazard models to investigate the association between residential pollution (single and multi-pollutant models) and asthma incidence defined as first ever hospital admission, adjusting for sex, smoking (status, duration, intensity), body mass index, marital status, employment, education and income on a neighbourhood level. Results: Of 50,163 persons, 888 developed asthma during the mean follow-up of 15.6 years. The mean concentrations of PM2.5, NO2 and BC were 10.9 μg/m3, 21.7 μg/m3 and 0.98 10-5/m, respectively. Statistically significant associations were found with NO2 and BC with adjusted hazard ratios and 95% CIs of 1.14 (1.04-1.25) per 10 µg/m3 and 1.15 (1.03-1.28) per 0.5 10-5/m, nonsignificant positive with PM2.5 (1.18; 0.91-1.53) per 5 μg/m3, and none with O3. The NO2 estimate remained unchanged in two-pollutant models with PM2.5, O3, or BC, whereas the BC estimate remained robust in the model with PM2.5 or O3, but attenuated in the model with NO2. The association with PM2.5 attenuated to negative in models with NO2 or BC. Conclusion: Long-term exposure to NO2 and BC was associated with asthma onset in adults, even at levels below current EU limit values.